Photo by: Arnulfo Franco
A Panama border police officer questions two migrants from India at a police station in the Darien province on the border with Colombia, in Yaviza, Panama. (AP Photo/Arnulfo Franco)

Robert Mueller’s special counsel investigation into Russian meddling in the 2016 election has cost $6.7 million during the first four and a half months of the probe. Click to see past independent counsel investigations guilty of racking up high bills.